User Reviews

Weaknesses: Fork seems loose and rattles. I thought at first the headset was loose.

Bottom Line:

I chose this bike for my latest electric conversion for the strong frame, large wheels, tall gearing, and hydraulic discs. I was able to mount 29x2 puncture resistant road tires, but the clearance to the front derailleur is tight. It only took me four tries to seal the front rim while converting to tubeless. With the suspension fork, 35 psi in the tires, and a Thudbuster seatpost, this bike is comfortable enough for everyday commuting.

I'm not sure about the manufacturing precision of the brakes, but this is among the lowest costing bike with hydraulic discs. I had to readjust the front after removing the wheel once, and the discs look slightly warped. For the road, they work very well. I have no problem slamming them on stopping at a light at the bottom of a hill.

I also had a lot of fun mounting the rear battery rack. The rear caliper was slightly in the way. It took a few washers and longer screws to mount securely.

Strengths: Although it looks more like a mountain bike with skinny knobby tires, don't be fooled. The bike is FAST. It will pretty much take anything the road has to offer and doing it smoothly. Other than the knobbies on the road, the bike gets 4.5 outta 5 in my book. Traction was surprisingly very good uphill as well. I don't think I slipped once, unlike my Rigid with the Kenda the SB8's, if I stood up at all to climb, I’d lose traction. I also think the non slippage is due to the larger 700x38 tires. More surface to contact to the ground.

Weaknesses: The Suntur fork with 63mm of travel is fine for most mild trail applications. For rock gardens and fast 30+mph down hills, this fork can be pretty uncomfortable. The 63mm of travel bottoms out on really hard hits and with just sitting on the bike, it sags about 30mm so in reality, you are getting only 33mm of travel. The only other weakness is that you are limited to going only a 29x2.0 rear tire and nothing wider or it will have no clearance for the front derailer. That is if you wanna go more hardcore MTBing, then i would recommend get a MTB.

Bottom Line:

Overall, the 8.4 did its job. Most riders told me I should have just gotten a mountain bike since I ride the mountain at least twice a week, get a purpose-built bike, etc., etc. I think that is just what I have done. Its purpose WAS to do BOTH Road and Mountain. And to test the 8.4 on the Loop is a great indicator of how the DS 8.4 can handle the abuse. The tires held up, but would definitely change them to wider tires if you plan on going mountain biking a lot. Same thing with on-road, if you plan on going faster, more on the road, go with the skinnier slicks. So to conclude my review and thoughts, the Trek DualSport 8.4 delivered. Those Trek Engineers along with Mr. Fisher himself did a great job! The only other thing that happened was the lock out switch popping off after bunny hopping over a branch. I didn’t notice this until I was done with the ride and saw it was gone. Luckily, it was on the ground at the beginning of the ride, but been run over by bikes and whatever else that went on the path. I can totally see why the remote lock out would be the better choice..the switch is plain CHEAP. Fail on this part. Nothing to hold the switch in but friction..so i put silicon on it to prevent it from popping out..hopefully it stays. I do like the remote lock out idea. For now, now that I know the 8.4 can take what I have to give it, I will be happy going to the Fullerton Loop and the Santa Ana River Trail for a while, enjoying the ride and staying fit.

Related 8.4 DS Forum Posts

Hi All,
I'm brand new to MTBing. Took a basic skills course yesterday with my Trek DS 8.4 (2012 model? white/black/gold).
The other riders in the group all used 'legit' mountain bikes, with wider tires than my DS.
What wheel/tire combo would you recommend for this bike for a beginner MTBer?
F ... Read More »

Hey folks,
A bud of mine had his almost brand new 2013 TREK 8.4 DS Gary Fisher series / 17.5 inch frame with Shimano components / SN: WTU149C7534G stollen outside the Silver City theatre at Masonville Mall around 2 pm. Locked up at a rack and gone when he returned.
no security video available un ... Read More »